Information Page of the Netherlands Color Synesthesia (NeCoSyn) Project  Nederlands


We manufacture stories, after all,
from the fleeting sensory material that bombards us at every instant.
(Siri Hustvedt 2003)

fragment uit animatie door Peter Struycken

Color synesthesia is the experience of color evoked by a stimulation of another sense modality than the eyes. Examples are experiences of colored letters and numbers, colored music and sounds, colored tastes and odors, colored emotions and pain, etcetera.

The Milanese artist Giuseppe Arcimboldo performed the earliest known experiment with color synesthesia at the court of Rudolf II in Prague around 1590. The first scientific study into the phenomenon of colored hearing was taken up by the German doctor Sachs in 1812. He studied the color photisms that were evoked by numbers, days of the week, letters and music. In the eighteenth and nineteenth century artistic and scientific studies into synesthesia developed along separate lines. Nonetheless they had a lot in common. They were dealing with the same human perceptions, but with different methods.

In the Netherlands Color Synesthesia (NeCoSyn) project artist Clara Froger and psychological researcher Crétien van Campen have been using methods from both disciplines. The aim was to explore the color aspects of synesthesia in more detail.

In their first cooperative experiments they established that color synesthesia is very different from most color associations. For instance, whereas most people associate the word SEA with a blue color, a synesthete can see the word as follows SEA, because the letter S is red, the letter E is yellow and the letter A is pinkish.

A good way to find out if you are a color word synesthete is to describe the colors of abstract words to your self. (See the  self-test (in Dutch)). In the cases of colored music and numbers this is, by their abstract nature, less a problem. Colored music is most of the time abstract enough unless the composer uses programmatic themes (think of Vivaldi’s Four Seasons). And in the western culture, numbers are seldom associated with colors.

Froger and Van Campen found that synesthetic colors are not one-dimensional (like ‘the letter A is red for me’), but multidimensional (‘the letter A has a dark, highly saturated bluish red color tone for me’). Like color perception, a synesthetic color perception has three dimensions: blackness (lightness), saturation and color tone.

Synesthetes have different sensitivities for these dimensions. Many people are sensitive for the brightness of letters (e.g. a dark sound of the letter U or a light sound of the letter E). But few are sensitive to the color tones of letters (a blue reddish A). That applies to sounds (music), tastes and odors too, as they found in our experiments with synesthetes.

Synesthetes differ in their experiences of colors and color dimensions for the same stimuli. For instance when two synesthetes listen to the same chord played on a harpsichord, they see different images. One person sees a number of thin, erratic short hard reddish lines in one specific spot against a full black background, while the other person sees  two golden grainlike granular lines that run over into broad glimmering black lines. This fact set us on the track to visualize the personal profiles of color synesthetes.

Generally, synesthetes are more involved in creative professions than non-synesthetes. This led us to the idea to ask synesthetes to paint their colored words, colored sounds and colored tastes. Pictures of a few paintings can be viewed here. The paintings show that synesthetic colors are moving in space too.

We continue our research along the less known colored paths of the senses with the motto of Colored senses: not only vision but all senses appear colorful. When you are interested in our research or in your personal profile of color synesthesia, please contact Crétien van Campen.

Thema Plaats & datum Inhoud
London 4/2005 Spatial Aspects of Colour Synaesthesia. Paper presented the UK Synaesthesia Association Annual Meeting, London 15-17 april 2005
New York 5/2003 Combining Artistic and Scientific Perspectives in the Study of Synesthesia. Paper presented at the Third Annual National Meeting of the American Synesthesia Association, 2-4 May 2003.
Rotterdam 4/2003 Verslag Synesthesiedag 5 April 2003.
San Francisco 8/2003 Personal Profiles of Color Synesthesia: Developing a Testing Method for Artists and Scientists. Leonardo 36:4 (2003) 291—294.
San Diego 5/2002 Profiles of Color Synesthesia. The NeCoSyn Method. Paper presented at the Second Annual National Meeting of the American Synesthesia Association, 17-19 May 2002.
Utrecht 11/2001 Assessing the strenght of color synesthesia in words, music, taste and odor perception Development of the NeCoSyn Method. Report, November 2001.


Amsterdam 10/2001 Oranje tuba's, volle sprot en lichte honing. Nieuwe gevallen van kleursynesthesie door meer verfijnde meting Psychologie Magazine, oktober 2001.
Utrecht 7/2001 Helderheid, verzadiging en toon van kleursynesthesie, Kleurenvisie, zomer 2001.
Utrecht 1999 De kleur van woorden, Kleurenvisie 1999, 6, 12-14
Maastricht/Utrecht 1998 Verrassende resultaten synesthesie-experiment. Kleurenvisie 1998, 5, 5-7.  
fragment uit animatie door Peter Struycken
San Francisco 1/1999 Artistic and Psychological Experiments with Synesthesia. Leonardo vol. 32, nr. 1 (1999) 9-14.
Amsterdam 9/1998 Kleuren zien met je achterhoofd. Psychologie Magazine, sep 1998, 14-17.
Maarssen 12/1996 Gedrogeerde deuren van de waarneming. Psychologie & Maatschappij 77, 1996, vol. 20., nr. 4, 374-387
Utrecht 3/1996 De verwarring der zintuigen. Artistieke en psychologische experimenten met synesthesie. Psychologie & Maatschappij 74, 1996, vol. 20, nr. 1, 10-26.

Information: Crétien van Campen